Substantial handling improvements can be made to the 240SX by lightening and strengthening the chassis.
240SX Chassis Lightening
You can reduce the weight of the car by removing unnecessary parts and replacing heavy components with lighter aftermarket parts.
The following is a list of parts that you may consider removing and their weights:
| Sound deadening material: | 39.8 lbs. |
|---|---|
| A/C system: | 29.2 lbs. |
| Spare tire: | 28.0 lbs. |
| Hatch cover, speaker panels, and rear floor mats: | 23.8 lbs. |
| HICAS system: | 22.4 lbs. |
| Back seats: | 20.8 lbs. |
| Automatic seat belts: | 20.0 lbs. |
| ABS system: | 19.0 lbs. |
| Stereo and speakers: | 16.8 lbs. |
| Carpeting: | 11.8 lbs. |
| Jack tools and jack cover: | 6.4 lbs. |
| Total: | 238.0 lbs. |
The following is a list of parts that you can replace with lighter aftermarket components to save weight:
| Product | Possible Replacement Parts | Price |
|---|---|---|
| Front seats | Bride ZETA III Seat Sparco Speed Seat | $800 |
| Battery | Buddy Club Racing Spec Battery Braille Racing Battery | $150 |
| Hood | Seibon OEM Style Carbon Fiber Hood (S13) VIS Invader Type 6 Carbon Fiber Hood (1995-96 240SX) | $520 |
240SX Chassis Strengthening
Increasing 240SX chassis rigidity is critical for building a good handling car. If the car flexes, suspension geometry changes. Therefore, even if you have a great suspension setup on your car, it will be ruined by inconsistent flexing of the chassis.
The weak points in the 240SX chassis are around the firewall area and the rear hatch area in the S13 fastback. It is easy to get carried away with adding all sorts of stiffening bars and braces. However, many of these parts make very little difference and only add additional weight to your car.
Below, I list some 240SX body kit components that noticeably improve steering response and overall handling. If you want to stiffen the chassis as much as possible, the best option is stitch welding the frame lines and installing a roll cage. This should only be necessary for a high-horsepower car or one that you plan to race on the track often.
| Product | Effect | Price |
|---|---|---|
| SPL Front Fender Brace | Reduces flex in the firewall area | $260 |
| NISMO Power Brace | Stiffens lower front of chassis | $190 |
| Okuyama Type-I Aluminum Front Strut Bar | Stiffens front of chassis | $210 |
| DC Sports Rear Carbon Steel Strut Bar | Stiffens rear of chassis | $165 |